Pacifica’s newest hiking trail is a step back into history, both ancient and modern, showcasing striking views of the Pacific and the forces that shape its ongoing, often destructive encounter with the California coast.

The sometimes fog-shrouded and always breathtaking Devil’s Slide Trail – which opened to the public March 27 and was formerly a perilous section of state Highway 1 south of San Francisco – is generously called a trail. It is mostly a gently sloping, paved roadway with easy access for hikers of all skill levels, as well as bicyclists and equestrians.

The northern part of the path wends through slanting layers of gray and brown sediment as old as 60 million years, forced upward from the ocean floor through the grinding of the Pacific and North American tectonic plates. The southern section consists of sturdier granite pushed northward from what is now Southern California. Between the tectonic forces pushing them together and the relentless surf, Devil’s Slide is fitfully collapsing into the sea.

The modern history of the area began in the late 19th century with the creation of a roadway between Pacifica and Montara that was to become the Ocean Shore Railroad, a project that was halted in 1920 due in part to damage from the 1906 earthquake that devastated San Francisco. Highway 1, also known as the Pacific Coast Highway, was finished in 1937 and only three years later, the first landslide closed the highway at Devil’s Slide.

After years of subsequent landslide closures and debate about the environmental impacts of a bypass, San Mateo County voters approved a measure in 1996 that resulted in the completion of the nearby $439 million Tom Lantos Tunnels project in 2013. Remaking the bypassed highway into a portion of the California Coastal Trail cost an estimated $2 million, according to a parks official, though visitors can enjoy it for free.

The trail area is now a haven for nesting seabirds and peregrine falcons, a viewing site for migrating whales, and a lookout over sweeping cliffs, windswept trees, crashing waves and ever-shifting mountainsides.

Efforts have been made to stabilize and contain the landslide areas, but parks officials acknowledge that the threat of “catastrophic slide” remains, in which case the trail could be briefly closed or even someday lost.

With the geologic future of this coastline yet to be determined, it may be best to witness its grandeur on the Devil’s Slide Trail while you can.

IF YOU GO

Devil’s Slide Trail

Small parking lots are at the northern and southern ends of the trail, accessible via state Highway 1 on either side of the Tom Lantos Tunnels, beginning at 8 a.m.; closing times change seasonally. Free shuttles are available from Pacifica on weekends. For more information, visit www.smcoparks.org. For out-of-town visitors, Pacifica offers several hotel and dining options.